Air precleaners that separate heavier-than-air particles from the air to be used in combustion engines, ventilation systems, and any apparatus that draws in air laden with heavier-than-air debris are known. All of these known air precleaners are functional, but do not address all the needs of electronically controlled combustion engines, or other apparatus that draw in air laden with heavier-than-air debris for a precleaner which adds no or minimal air intake restriction while providing high particle separating efficiency over the broad airflow range with which they are used. An object of the present invention is to provide an improved air precleaner device and more efficient method for centrifugally ejecting heavier-than-air particulate debris from the air stream delivering clean air with positive pressure or no or minimal airflow restriction to the apparatus the precleaner is installed on, overcoming the aforementioned disadvantages of the known air precleaners. More particularly, an object of the present invention is to provide an improved air precleaner device and method, which meet or exceed the requirements for use of the air precleaner device in connection with an inline airflow provider for any apparatus requiring or benefiting from a clean air flow such as combustion engines, fixed airflow provider for heat exchangers and heating and air conditioning systems, and total airflow applications for ventilation systems. The air precleaner device and method of the invention offer significant improvements in debris removal and provide positive airflow as compared with conventional atmospheric ejective air precleaners. Instead of depending on the available airflow to drive the mechanical separation process, (which adds to the restriction of the system,) the invention delivers efficient atmospheric precleaning while adding no additional restriction to the apparatus on which the precleaner is installed. In fact, the air precleaner device of the invention may "supercharge" an air intake system minimizing or eliminating overall initial restriction. A fan assembly draws debris laden air into the precleaning system. The debris-laden air is then accelerated in a radial pattern where centrifugal forces acting on the debris are enhanced. These centrifugal forces then discharge the heavier-than-air debris out of a strategically placed ejection port back into the atmosphere. The air precleaner device maintains a positive air pressure on the downstream side such as a filter media, heat exchanger core, or ventilation system; therefore, the invention precleaning device does not suffer performance losses associated with cyclic airflow demands like all other atmospheric precleaners do. Instead, the air precleaner device and method of the invention provide full-time efficient precleaning in the 90% plus range of efficiency.
Specifically, a powered low restriction air precleaner device according to the invention comprises a fan located in the device for drawing debris laden air into the device. The fan includes a fan blade and a motor for rotating the fan blade. Means are provided for spinning the debris laden air drawn into the air precleaner device to form a rotating flow pattern that stratifies the debris laden air with the most massive particles of debris in the outermost orbits of the rotating flow pattern of debris laden air. An ejection duct of the device ejects debris from the rotating flow of the debris laden air in the air precleaner device to clean the air. An air outlet of the device flows the cleaned air from the device to an apparatus to be supplied with cleaned air.
The present invention also comprises an apparatus for providing a flow of clean air, the apparatus comprising, in combination, a powered low restriction air precleaner device according to the invention, in combination with an arrangement for applying a suction to the air outlet of the device for assisting drawing the debris laden air into the air precleaner device. The arrangement for applying a suction to the air outlet of the device can be an air intake of a combustion engine or another fan located downstream of the air outlet of the device, such as on the far side of a radiator for cooling a machine, or on the clean side of an air filter of an air intake system of a cab.
A method for centrifugally ejecting heavier-than-air particulate debris from debris laden air according to the invention for providing clean air to an apparatus comprises the steps of drawing debris laden air into an air precleaner device with a fan located in the device, spinning the debris laden air in the air precleaner device to form a rotating flow pattern that stratifies the debris laden air with the most massive particles of debris in the outermost orbits of the rotating flow pattern of debris laden air, ejecting debris in the rotating flow pattern of debris laden air in the air precleaner device from the air precleaner device to clean the air, and flowing cleaned air to an air outlet of the device.
These and other objects, features and advantages of the present invention will become more apparent from the following description when taken in connection with the accompanying drawings, which show, for purposes of illustration only, one preferred embodiment in accordance with the present invention.